There will be no small -- on this camping trip in fact for the eight explorers on that GAO's ultimate survival Alaska. There will be no food at all. Unless they find it trekking through 3000 miles of Alaska's most desolate terrain they're only prize is survival. And here's AB c.'s G -- natives. 08. Floors turned contestants we got her -- risking their lives in a test of survival and I don't know well. Living off the land for two -- and -- 3000 miles of Alaska while destroying their -- their life. The pool on ten different heights -- you're working as teams they must get from point eight to point B in under 72 hours. Missing the deadline means missing a flight on the extraction -- -- -- Maria ago which could leave them stranded for days. 42 of the contestants this hardcore life is second nature. Brothers Delis and -- C he met -- outside on a rainy day. They spent their childhood in Alaska's rugged outdoors but we're out here in Central Park in the ring if you would have -- no other way. Absolutely if they -- up where. According to the wilderness -- not a weekend trip or it. Didn't like this special things this just will be did we look -- like dogs and editor in fact their grandfather co founded the famous Iditarod sled dog race. Last year Dallas became the youngest person ever to win it. This year he convinced his brother to join him on that NGOs ultimate survival Alaska. It kind of got me -- to enact house on -- where they they -- -- guy short the last second so I got a phone call an hour later I was on the road. The spirit and the body are tested now setting the pace for him is too easy for the rest of us humans. Deng and catch your breath horns and a line. It literally the once a lifetime experience you see all the extremes of -- -- -- and that. Mentality -- the best part -- herself you do admit nothing else to worry about -- -- and they -- forging for food. It's very primal existence is very fun in that regard. He's not kidding when he says foraging for food on their first -- attack -- -- everything his way the Brothers. Can't even light a fire because of the downpour they only have two boxes of matches for the entire trip. You know Hotmail is number one priority right now. If we don't get this fire going we'll -- going hungry. The two were left eating uncooked rice and beans rain -- -- for the fires zero. Lots of tastiest -- I never had those calories and it. Much needed calories or just the beginning. You're basically rocks that can be extremely frustrating your way you're cold you don't know where you're going. And at the end of the challenges. Out there is no crimes. Like -- a lot of people -- watching this show and they say why do this why go through all. Easy answer is because it put yourself in the situation -- you really test it -- How you react when the rubber really hits the road I -- that it's an opportunity to look at adversity as. Find a way out an amazing journey if you can make for Nightline -- -- Benitez in New York. Things you know ultimate survival Alaska airs Sundays on the National Geographic channel.

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